DRX operation for UL/DL reconfiguration

ABSTRACT

In embodiments, apparatuses, methods, and storage media may be described for identifying subframes in a radio frame on which a UE may receive a Physical Downlink Control Channel (PDCCH) or enhanced PDCCH (ePDCCH) transmission. Specifically, the UE may receive multiple indications of uplink/downlink (UL/DL) subframe configurations and identify one or more subframes in which the UE may receive the PDCCH or ePDCCH transmission. The UE may then monitor one or more of the identified subframes and base discontinuous reception (DRX) timer functionality on one or more of the identified subframes.

CROSS REFERENCE TO RELATED APPLICATION

The present application is a continuation of U.S. patent applicationSer. No. 14/991,696, filed Jan. 8, 2016, entitled “DRX OPERATION FORUL/DL RECONFIGURATION,” which is a continuation of U.S. patentapplication Ser. No. 14/316,188, filed Jun. 26, 2014, entitled “DRXOPERATION FOR UL/DL RECONFIGURATION,” which claims priority to U.S.Provisional Patent Application No. 61/879,014, filed Sep. 17, 2013,entitled “Advanced Wireless Communication Systems and Techniques”. Theentire disclosures of which are hereby incorporated by reference intheir entireties.

FIELD

Embodiments of the present invention relate generally to the technicalfield of discontinuous reception (DRX) functionality in radio frames.

BACKGROUND

The background description provided herein is for the purpose ofgenerally presenting the context of the disclosure. Work of thepresently named inventors, to the extent it is described in thisbackground section, as well as aspects of the description that may nototherwise qualify as prior art at the time of filing, are neitherexpressly nor impliedly admitted as prior art against the presentdisclosure. Unless otherwise indicated herein, the approaches describedin this section are not prior art to the claims in the presentdisclosure and are not admitted to be prior art by inclusion in thissection.

DRX functionality may be used to save battery power in a user equipment(UE) of a wireless network by skipping reception of signals in thephysical downlink control channel (PDCCH) or enhanced PDCCH (ePDCCH).Specifically, the UE may monitor one or more radio subframes of theradio frame in a wireless network for a PDCCH/ePDCCH signal. However, inuplink (UL) subframes of the radio frame, the UE may not monitor for aPDCCH/ePDCCH signal. Additionally, DRX functionality may involve one ormore timers, and if those timers have expired or are not running, the UEmay not monitor for a PDCCH/ePDCCH signal.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will be readily understood by the following detaileddescription in conjunction with the accompanying drawings. To facilitatethis description, like reference numerals designate like structuralelements. Embodiments are illustrated by way of example and not by wayof limitation in the figures of the accompanying drawings.

FIG. 1 schematically illustrates an example of a network comprising a UEand an eNodeB (eNB), in accordance with various embodiments.

FIG. 2 illustrates an example of options for monitoring differentuplink/downlink (UL/DL) subframe configurations, in accordance withvarious embodiments.

FIG. 3 depicts an example process for monitoring PDCCH transmissions invarious UL/DL subframe configurations, in accordance with variousembodiments.

FIG. 4 schematically illustrates an example system that may be used topractice various embodiments described herein.

DETAILED DESCRIPTION

In embodiments, apparatuses, methods, and storage media may be describedfor identifying subframes in a radio frame on which a UE may receive aPDCCH/ePDCCH transmission (herein collectively referred to as a PDCCHtransmission). Specifically, the UE may receive multiple indications ofUL/DL subframe configurations and identify one or more subframes inwhich the UE may receive the PDCCH transmission. The UE may then monitorone or more of the identified subframes and base DRX timer functionalityon one or more of the identified subframes.

In some embodiments, the UE may receive conflicting UL/DL subframeconfigurations, for example, in a system information block type 1 (SIB1)message, a PDCCH transmission, or radio resource control (RRC)signaling. For example, a UL subframe in one of the UL/DL configurationsmay be a DL or special subframe (i.e., a subframe that may include aDownlink Pilot Time Slot (DwPTS)). The UE may identify, based on theconflicting UL/DL subframe configurations, which subframes to use forthe PDCCH monitoring and the DRX functionality.

In the following detailed description, reference is made to theaccompanying drawings that form a part hereof wherein like numeralsdesignate like parts throughout, and in which is shown by way ofillustration embodiments that may be practiced. It is to be understoodthat other embodiments may be utilized and structural or logical changesmay be made without departing from the scope of the present disclosure.Therefore, the following detailed description is not to be taken in alimiting sense.

Various operations may be described as multiple discrete actions oroperations in turn, in a manner that is most helpful in understandingthe claimed subject matter. However, the order of description should notbe construed as to imply that these operations are necessarily orderdependent. In particular, these operations may not be performed in theorder of presentation. Operations described may be performed in adifferent order than the described embodiment. Various additionaloperations may be performed and/or described operations may be omittedin additional embodiments.

For the purposes of the present disclosure, the phrase “A and/or B”means (A), (B), or (A and B). For the purposes of the presentdisclosure, the phrase “A, B, and/or C” means (A), (B), (C), (A and B),(A and C), (B and C), or (A, B and C).

The description may use the phrases “in an embodiment,” or “inembodiments,” which may each refer to one or more of the same ordifferent embodiments. Furthermore, the terms “comprising,” “including,”“having,” and the like, as used with respect to embodiments of thepresent disclosure, are synonymous.

FIG. 1 schematically illustrates an example wireless network 100(hereinafter “network 100”) in accordance with various embodiments. Thenetwork 100 may include a UE such as UE 110 coupled with an eNB 105. Insome embodiments, the network 100 may be an access network of a thirdgeneration partnership project (3GPP) long term evolution (LTE) networksuch as evolved universal terrestrial radio access network (E-UTRAN). Inthese embodiments the eNB 105 may be a 3GPP-defined eNodeB (alsoreferred to as an evolved NodeB) configured to wirelessly communicatewith the UE 110 using a wireless protocol such as the 3GPP LTE wirelessprotocol.

As shown in FIG. 1, the UE 110 may include a transceiver module 122,which may also be referred to as a multi-mode transceiver chip. Thetransceiver module 122 may be configured to transmit and receivewireless signals. Specifically, the transceiver module 122 may becoupled with one or more of a plurality of antennas 125 of the UE 110for communicating wirelessly with other components of the network 100,e.g., eNB 105 or another UE. The antennas 125 may be powered by a poweramplifier 130 which may be a component of the transceiver module 122, orcoupled with the transceiver module 122 and generally between thetransceiver module 122 and the antennas 125 as shown in FIG. 1. In oneembodiment, the power amplifier 130 may provide the power for alltransmissions on the antennas 125. In other embodiments, there may bemultiple power amplifiers on the UE 110. The use of multiple antennas125 may allow for the UE 110 to use transmit diversity techniques suchas spatial orthogonal resource transmit diversity (SORTD),multiple-input multiple-output (MIMO), or full-dimension MIMO (FD-MIMO).

In certain embodiments the transceiver module 122 may include acommunication module 120, which may be referred to as a broadbandmodule. Communication module 120 may contain both transmitter circuitry145 configured to cause the antennas 125 to transmit one or more signalsfrom the UE 110, and receiver circuitry 150 configured to cause theantennas 125 to receive one or more signals at the UE 110. In otherembodiments, the communication module 120 may be implemented in separatechips or modules, for example, one chip including the receiver circuitry150 and another chip including the transmitter circuitry 145. In someembodiments the signals may be cellular signals transmitted to orreceived from a 3GPP eNB such as eNB 105. In some embodiments, the UE110 may include a processor 175 coupled to the transceiver module 122.The processor 175 may further be coupled with or include a DRX module180 that may be configured to perform one or more of the DRX functionsdescribed in further detail below.

Similarly to the UE 110, the eNB 105 may include a transceiver module135. The transceiver module 135 may be further coupled with one or moreof a plurality of antennas 140 of eNB 105 for communicating wirelesslywith other components of the network 100, e.g., UE 110. The antennas 140may be powered by a power amplifier 160 which may be a component of thetransceiver module 135, or may be a separate component of the eNB 105,and generally positioned between the transceiver module 135 and theantennas 140 as shown in FIG. 1. In one embodiment, the power amplifier160 may provide the power for all transmissions on the antennas 140. Inother embodiments, there may be multiple power amplifiers on the eNB105. The use of multiple antennas 140 may allow for the eNB 105 to usetransmit diversity techniques such as SORTD, MIMO, or FD-MIMO. Incertain embodiments the transceiver module 135 may contain bothtransmitter circuitry 165 configured to cause the antennas 140 totransmit one or more signals from the eNB 105, and receiver circuitry170 configured to cause the antennas 140 to receive one or more signalsat the eNB 105. In other embodiments, the transceiver module 135 may bereplaced by transmitter circuitry 165 and receiver circuitry 170 whichare separate from one another (not shown). In some embodiments, thoughnot shown, the transceiver module 135 may include a communication modulesuch as communication module 120 that includes the receiver circuitry170 and the transmitter circuitry 165.

As described above, DRX functionality may be used in a network such asnetwork 100 to preserve the battery life of a UE such as UE 110.Specifically, the DRX functionality may preserve the battery by allowingthe UE to enter a low power or sleep state where the UE does not monitorfor a DL signal on the PDCCH. Dependent on how predictable the trafficarrival rate may be in the network 100, and based on quality of service(QoS) requirements associated with the radio bearer of the network 100,an eNB such as eNB 105 may configure a single DRX interval for the UE touse in LTE systems such as network 100. It will be noted that the belowdiscussion that refers to the PDCCH or PDCCH signals may additionallyapply to ePDCCH or ePDCCH signals. However, for ease of reference, onlythe PDCCH will be referred to below.

In some embodiments, the network 100 may be configured as a timedivision duplexing (TDD) network. Specifically, in some embodiments aradio frame may be 10 milliseconds (ms) long. The radio frame mayinclude 10 subframes of the radio frame, each subframe being 1 ms long.A subframe of the radio frame may be designated as a UL, a DL, or aspecial subframe. A UL subframe may be a subframe designated for atransmission from the UE such as UE 110 to an eNB such as eNB 105. A DLsubframe may be a subframe designated for a transmission from the eNB105 to the UE 110. A special subframe may be a subframe that may carryor include a DwPTS transmitted from the eNB 105 to the UE 110.

Whether a subframe of a radio frame is designated as a UL subframe, a DLsubframe, or a special subframe may be indicated by a UL/DLconfiguration of the radio frame. Table 1, below, depicts various UL/DLconfigurations that may be used in some embodiments. The UL/DLconfigurations depicted in Table 1 may specifically apply to 3GPP radioframes with Frame Structure 2. In other embodiments, other UL/DLconfigurations may be used. In Table 1, “D” may indicate a DL subframe.“U” may indicate a UL subframe. “S” may indicate a special subframe

TABLE 1 UL/DL Subframe Number Configuration 0 1 2 3 4 5 6 7 8 9 0 D S UU U D S U U U 1 D S U U D D S U U D 2 D S U D D D S U D D 3 D S U U U DD D D D 4 D S U U D D D D D D 5 D S U D D D D D D D 6 D S U U U D S U UD

For TDD carriers in such TDD networks, DRX operation may be based onsubframes where a PDCCH signal may be received by the UE. Specifically,the UE may receive a PDCCH signal either in a DL subframe, or a specialsubframe (i.e., a subframe that may include a DwPTS), hereincollectively referred to for ease of reference as “PDCCH subframes.”Specifically, the UE may monitor for the PDCCH only in the PDCCHsubframes, and not monitor for the PDCCH signal in a UL subframe.Further, the UE may monitor for the PDCCH in the PDCCH subframes onlywhen an active DRX related timer is running, or an uplink grant ispending.

As described below, a running DRX related timer may only incrementduring the PDCCH subframes in which it is running, and not incrementduring a UL subframe. For example, a DRX related timer with a value of xin PDCCH subframe y may increment to value x+1 in PDCCH subframe y+1.The values of x and y may be irrespective of whether there are one ormore UL subframes between PDCCH subframe y and PDCCH subframe y+1. Oncethe DRX timer reaches a set value, the timer may expire as describedbelow.

In embodiments, there may be three DRX timers used in the TDD network100. These timers may include a DRX duration timer (referred to hereinas onDurationTimer), a DRX inactivity timer (referred to herein asDRX-InactivityTimer), or a DRX retransmission timer (referred to hereinas DRX-RetransmissionTimer). The onDurationTimer may indicate the numberof PDCCH subframes in the radio frame that the UE 110 should monitor fora PDCCH signal. For example, if the subframes in the radio frame arenumbered 0-9, an onDurationTimer value of 2 may indicate that the UE 110should monitor subframes 0 and 1 for a PDCCH signal (assuming thatsubframes 0 and 1 are PDCCH subframes).

The DRX-InactivityTimer may indicate the number of PDCCH subframes thatthe UE 110 should monitor for a PDCCH signal after a first PDCCH signalis received in the radio frame.

As a concrete example, assume that the radio frame is configured withUL/DL configuration 0, the value of onDurationTimer is 2, and the valueof DRX-InactivityTimer is 2. As can be seen in Table 1, subframes 0, 1,5, and 6 may be PDCCH subframes. Subframes 2-4 and 7-9 may not be PDCCHsubframes.

Based on onDurationTimer, the UE 110 may monitor subframes 0 and 1(which are DL and special subframes, respectively, and therefore bothPDCCH subframes) for a PDCCH signal. If the UE 110 does not receive aPDCCH signal in subframes 0 or 1, then the UE 110 may not monitorsubframes 2-9 for a PDCCH signal, for example, by entering the low-poweror sleep mode.

However, if the UE 110 receives a PDCCH signal in subframe 0, then theUE may stay awake beyond the value indicated by onDurationTimer andmonitor PDCCH subframes based on the DRX-InactivityTimer value. Forexample, based on the value of the DRX-InactivityTimer, which is 2, theUE 110 may monitor two additional PDCCH subframes past subframe 0 for aPDCCH signal. In this example, then the UE 110 may monitor PDCCHsubframes 0, 1, and 5 for a PDCCH signal. As noted above, subframes 2-4may not be PDCCH subframes, and so the UE may not monitor for a PDCCHsignal in subframes 2-4, for example, by entering a DRX low-power orsleep mode. Additionally, upon expiration of the DRX-InactivityTimer,the UE may enter the DRX low-power or sleep mode for subframes 6-9.Similarly, if the UE 110 receives a PDCCH signal in subframe 1, then theUE 110 may, based on the DRX-InactivityTimer, monitor PDCCH subframes 5and 6 for a PDCCH signal, and enter the DRX low-power or sleep mode forPDCCH subframes 2-4 and 7-9.

The DRX-Retransmission Timer may relate to the UE 110 monitoring for oneor more scheduled DL Hybrid Automatic Repeat request (HARQ)retransmissions. Specifically, with the DRX-Retransmission Timer, the UE110 may be configured to monitor PDCCH subframes for a PDCCH signal fromthe first possible instance of a HARQ retransmission as long as the UE110 or eNB 105 have schedulable pending retransmissions.

In some embodiments it has been observed that this semi-staticallocation of UL and DL subframes and the UL/DL configurations describedabove in Table 1 may not be appropriate for the current trafficsituation of the network 100, and therefore may result in unoptimizedspectrum utilization. Therefore, in some embodiments a radio frame mayinclude “flexible” subframes (also referred to as FlexSF). A flexiblesubframe may be a subframe that is capable of UL or DL traffic. In someembodiments, the direction of the flexible subframe may be dynamicallyconfigured by an eNB such as eNB 105. With these flexible subframes, theeNB 105 may be able to dynamically configure flexible subframes to matchthe current traffic situation of the network 100. The subframes may beappropriate, for example, in LTE networks such as a release 12 (Rel-12)LTE network configured to use enhanced interference mitigation andtraffic adaptation (eIMTA). In some embodiments, a flexible subframe maybe one or more of subframes 3, 4, or 6-9 of the radio frame.Specifically, in some embodiments subframes 3, 4, and 7-9 may be eitherUL or DL subframes. Subframe 6 may be a special subframe or a DLsubframe.

However, because certain subframes of the radio frame may be either ULor DL subframes, it may be difficult to identify which subframes of theradio frame are PDCCH subframes. It may be particularly difficult toidentify which subframes of the radio frame are PDCCH subframes ifmultiple UL/DL configurations are indicated by the eNB 105 to the UE110. Therefore it may be difficult to identify when a DRX timer shouldbe incremented, or when the UE 110 should be monitoring for a PDCCHsignal. It may also be inefficient for the UE 110 to monitor all PDCCHand flexible subframes for a PDCCH signal, because doing so maysignificantly decrease the battery life of the UE 110.

In some embodiments, three UL/DL configurations may be independentlysignaled by an eNB such as eNB 105 to a UE such as UE 110. First, theeNB 105 may signal a UL/DL configuration to the UE 110 in a SIB1message, herein referred to as the SIB1 UL/DL configuration. The SIB1UL/DL configuration may be applicable to a plurality of radio frames.

Secondly, the eNB 105 may signal a UL/DL configuration to a UE 110 in aPDCCH or ePDCCH message in a first subframe or higher-layer configuredsubframe of a radio frame. For ease of reference, the UL/DLconfiguration signaled in the PDCCH subframe will be referred to hereinas an “actual” UL/DL configuration. In some embodiments, the actualUL/DL configuration may only be applicable to the radio frame that thePDCCH subframe is a part of. For example, the actual UL/DL configurationmay be signaled in subframe 0 of the radio frame, and apply to thatradio frame. In other embodiments, the UL/DL configuration signal thenthe PDCCH subframe may be applicable to a subsequent radio frame.

Thirdly, the eNB 105 may signal a UL/DL configuration to the UE 110 viaradio resource control (RRC) signaling. This UL/DL configuration will bereferred to as a “DL-reference” UL/DL configuration. Similarly to theSIB1 UL/DL configuration, the DL-reference UL/DL configuration may beapplicable to a plurality of radio frames. The DL-reference UL/DLconfiguration may be generally applicable to a determination of DL HARQtiming associated with Physical Downlink Shared Channel (PDSCH)reception. In some embodiments, the DL-reference UL/DL configuration maybe associated with a HARQ round-trip time (RTT) that may be set to k+4subframes, where k is the interval between the DL transmission and thatUL transmission of associated HARQ feedback according to theDL-reference UL/DL configuration.

FIG. 2 depicts four different Options for identifying a UL/DLconfiguration that the UE 110 should use to monitor for a PDCCH signaland increment a DRX timer for a radio frame configured according toFrame Structure 2 and including flexible subframes. As shown in FIG. 2,subframes 0 and 5 may be DL subframes, subframe 1 may be a specialsubframe, and subframe 2 may be an uplink subframe according to FrameStructure 2. Additionally, subframes 3, 4, and 7-9 may be flexiblesubframes according to Frame Structure 2, wherein the subframes may beeither UL or DL subframes. Finally, subframe 6 may be either a specialor DL subframe according to Frame Structure 2. For ease of reference,assume that the configurations indicated in FIG. 2, for example, withrespect to Option 2, Option 3, and Option 4, refer to the UL/DLconfigurations indicated above in Table 1.

As a first, and simplest, Option (indicated in FIG. 2 as Option 1), theUE 110 may base PDCCH monitoring and DRX timer functionality only on thePDCCH subframes that are PDCCH subframes in each possible UL/DLconfiguration that may be indicated by the SIB1 message. As shown inFIG. 2 according to the subframes marked with an “X” for Option 1, PDCCHsubframes may be subframes 0, 1, 5, and 6. The reason that subframes 0,1, 5, and 6 may be PDCCH subframes for each possible UL/DL configurationmay be seen in Table 1, where for each of the seven UL/DL configurationsshown, subframes 0, 1, 5, and 6 may be either DL or special subframes.

As a second Option (indicated in FIG. 2 as Option 2), the UE 110 maybase PDCCH monitoring and DRX timer functionality only on the PDCCHsubframes that are identified as PDCCH subframes in the SIB1 UL/DLconfiguration. For example, in this option, if the SIB1 UL/DLconfiguration is UL/DL configuration 1 of Table 1, then the PDCCHsubframes may be subframes 0, 1, and 4-6. Both Options 1 and 2 mayprovide the benefit of allowing the DRX state at UE 110 to bepredictable, and help ensure no mismatch between the UE 110 and eNB 105due to counting static DL subframes only for DRX operation. Therefore,undesirable data loss may be avoided.

As a third Option (indicated in FIG. 2 as Option 3), the UE 110 may basePDCCH monitoring and DRX timer functionality only on the PDCCH subframesthat are identified as PDCCH subframes in the DL-reference UL/DLconfiguration. For example, in this Option, if the DL-reference UL/DLconfiguration is UL/DL configuration 2 of Table 1, then the PDCCHsubframes may be subframes 0, 1, 3-6, 8, and 9.

In some embodiments, it may be seen that Options 1, 2, or 3 may lead tothat PDCCH monitoring decoupling from the “PDCCH subframe” definitionused for legacy DRX timers. Specifically, flexible subframes may bemonitored for a PDCCH signal according to a common UL/DL configurationfor a plurality of UEs, but they may not be counted for the purposes ofthe DRX timer at UE 110.

As a fourth Option (indicated in FIG. 2 as Option 4), the UE 110 maybase PDCCH monitoring and DRX timer functionality only on the PDCCHsubframes that are identified as PDCCH subframes in the actual UL/DLconfiguration. For example, in this Option, if the actual UL/DLconfiguration is UL/DL configuration 3 of Table 1, then the PDCCHsubframes may be subframes 0, 1, and 5-9. This Option may have thebenefit of keeping the number of scheduling opportunities for the UE 110constant over time regardless of the changing of transmission directionin the flexible subframes, thereby optimizing UE battery consumption.

In some embodiments, for networks utilizing the Option 4, the UE 110 maymiss a common downlink control information (DCI) transmission for agroup of UE, which may result in misalignment between the active UE 110and eNB 105 with regard to UL/DL subframes of the actual UL/DLconfiguration being used. As a consequence, UE 110 and eNB 105 may fallout of sync on the DRX state and/or DRX timer, or follow different DRXpatterns. In some embodiments, the UE 110 may default to Option 1 as afallback position.

In some embodiments, different UL/DL configurations may be used fordifferent DRX timers. For example, the onDurationTimer andDRX-InactivityTimer may be based on a different UL/DL configuration thanthe DRX-RetransmissionTimer because the DRX-RetransmissionTimer may bemore directly related to HARQ operation of the network 100, while theother two timers are not. For example, the onDurationTimer andDRX-InactivityTimer may be optimized using Options 1, 2, or 4. Bycontrast, because the DRX-RetransmissionTimer is more closely related toHARQ retransmissions, the DL-reference UL/DL configuration describedwith respect to Option 3 may be more appropriate for that timer.

As can be seen in FIG. 2, one UL/DL configuration may indicate a PDCCHsubframe in a flexible subframe, while another of the UL/DLconfigurations indicates a UL subframe. For example, UL/DL configuration1, depicted with respect to Option 2, may indicate that flexiblesubframe 3 is a UL subframe, while UL/DL configuration 2, depicted withrespect to Option 3, may be a PDCCH subframe. However, by selecting oneof Options 1 through 4, the network 100 may be able to more effectivelyutilize DRX functionality and PDCCH monitoring in situations where oneof the UL/DL configurations received by the UE 110 conflicts withanother of the UL/DL configurations received by the UE 110.

FIG. 3 depicts an example process that may be performed by a UE such asUE 110. Initially, the UE 110 may receive indications of multiple UL/DLconfigurations applicable to subframes of a radio frame at 300. Forexample, the UE 110 may receive indications of one or more of the SIB1UL/DL configuration, the actual UL/DL configuration, or the DL-referenceUL/DL configuration.

Next, the UE 110 may identify DL subframes and subframes that mayinclude a DwPTS according to one of the received UL/DL configurations at305, and start a DRX timer at 310. The DRX timer may be, for example,one of the DRX timers described above. The DL subframes or DwPTSsubframes may be a PDCCH subframe as described above.

Next, the UE 110 may monitor the PDCCH or ePDCCH for a transmission inthe identified DL subframes and subframes that may include a DwPTS(i.e., the PDCCH subframes) while the DRX timer is running at 315.Additionally, the UE 110 may increment the DRX timer only in theidentified DL subframes and subframes that may include the DwPTS at 320,as described above. That is, a DRX related timer with a value of x inPDCCH subframe y may increment to value x+1 in PDCCH subframe y+1,regardless of whether there is a non-PDCCH (i.e., a UL) subframe betweenPDCCH subframe y and PDCCH subframe y+1. Once the DRX timer reaches aset value, the timer may expire as described above.

Embodiments of the present disclosure may be implemented into a systemusing any suitable hardware and/or software to configure as desired.FIG. 4 schematically illustrates an example system 400 that may be usedto practice various embodiments described herein. FIG. 4 illustrates,for one embodiment, an example system 400 having one or moreprocessor(s) 405, system control module 410 coupled to at least one ofthe processor(s) 405, system memory 415 coupled to system control module410, non-volatile memory (NVM)/storage 420 coupled to system controlmodule 410, and one or more communications interface(s) 425 coupled tosystem control module 410.

In some embodiments, the system 400 may be capable of functioning as theUE 110 as described herein. In other embodiments, the system 400 may becapable of functioning as eNB 105, as described herein. In someembodiments, the system 400 may include one or more computer-readablemedia (e.g., system memory or NVM/storage 420) having instructions andone or more processors (e.g., processor(s) 405) coupled with the one ormore computer-readable media and configured to execute the instructionsto implement a module to perform actions described herein.

System control module 410 for one embodiment may include any suitableinterface controllers to provide for any suitable interface to at leastone of the processor(s) 405 and/or to any suitable device or componentin communication with system control module 410.

System control module 410 may include memory controller module 430 toprovide an interface to system memory 415. The memory controller module430 may be a hardware module, a software module, and/or a firmwaremodule.

System memory 415 may be used to load and store data and/orinstructions, for example, for system 400. System memory 415 for oneembodiment may include any suitable volatile memory, such as suitabledynamic random-access memory (DRAM), for example. In some embodiments,the system memory 415 may include double data rate type four synchronousDRAM (DDR4 SDRAM).

System control module 410 for one embodiment may include one or moreinput/output (I/O) controller(s) to provide an interface to NVM/storage420 and communications interface(s) 425.

The NVM/storage 420 may be used to store data and/or instructions, forexample. NVM/storage 420 may include any suitable non-volatile memory,such as flash memory, for example, and/or may include any suitablenon-volatile storage device(s), such as one or more hard disk drive(s)(HDD(s)), one or more compact disc (CD) drive(s), and/or one or moredigital versatile disc (DVD) drive(s), for example.

The NVM/storage 420 may include a storage resource physically part of adevice on which the system 400 may be installed or it may be accessibleby, but not necessarily a part of, the device. For example, theNVM/storage 420 may be accessed over a network via the communicationsinterface(s) 425.

Communications interface(s) 425 may provide an interface for system 400to communicate over one or more network(s) and/or with any othersuitable device. The system 400 may wirelessly communicate with the oneor more components of the wireless network in accordance with any of oneor more wireless network standards and/or protocols. In some embodimentsthe communications interface(s) 425 may include the transceiver modules122 or 135.

For one embodiment, at least one of the processor(s) 405 may be packagedtogether with logic for one or more controller(s) of system controlmodule 410, e.g., memory controller module 430. For one embodiment, atleast one of the processor(s) 405 may be packaged together with logicfor one or more controllers of system control module 410 to form aSystem in Package (SiP). For one embodiment, at least one of theprocessor(s) 405 may be integrated on the same die with logic for one ormore controller(s) of system control module 410. For one embodiment, atleast one of the processor(s) 405 may be integrated on the same die withlogic for one or more controller(s) of system control module 410 to forma System on Chip (SoC).

In some embodiments the processor(s) 405 may include or otherwise becoupled with one or more of a graphics processor (GPU) (not shown), adigital signal processor (DSP) (not shown), wireless modem (not shown),digital camera or multimedia circuitry (not shown), sensor circuitry(not shown), display circuitry (not shown), and/or global positioningsatellite (GPS) circuitry (not shown).

In various embodiments, the system 400 may be, but is not limited to, aserver, a workstation, a desktop computing device, or a mobile computingdevice (e.g., a laptop computing device, a handheld computing device, atablet, a netbook, a smart phone, a gaming console, etc.). In variousembodiments, the system 400 may have more or less components, and/ordifferent architectures. For example, in some embodiments, the system400 includes one or more of a camera, a keyboard, a liquid crystaldisplay (LCD) screen (including touch screen displays), a non-volatilememory port, multiple antennas, a graphics chip, an application-specificintegrated circuit (ASIC), and speakers.

EXAMPLES

Example 1 may include a user equipment (UE) comprising: a processor toidentify, based only on downlink (DL) subframes and subframes thatinclude a downlink pilot time slot (DwPTS) in a first uplink/downlink(UL/DL) configuration in a plurality of received UL/DL configurations,DL subframes and subframes that include a DwPTS in a radio frame,wherein at least one of the DL subframes and subframes that include aDwPTS in the first UL/DL configuration is identified as a UL subframe inthe radio frame based on a second UL/DL configuration in the pluralityof received UL/DL configurations; and a discontinuous reception (DRX)module to: increment a running DRX timer based on one of the at leastone of the DL subframes and subframes that include a DwPTS; and monitorthe one of the at least one of the DL subframes and subframes thatinclude a DwPTS for a Physical Downlink Control Channel (PDCCH)transmission or an enhanced PDCCH (ePDCCH) transmission.

Example 2 may include the UE of example 1, wherein the UE is an enhancedinterference mitigation and traffic adaptation (eIMTA)-enabled UE.

Example 3 may include the UE of example 1, wherein the DRX timer is aDRX duration timer, a DRX inactivity timer, or a DRX retransmissiontimer.

Example 4 may include the UE of example 1, wherein the first or secondUL/DL configurations are a UL/DL configuration received by the UE in asystem information block type 1 (SIB1) message from an eNodeB (eNB), aUL/DL configuration received by the UE via radio resource control (RRC)signaling, or a UL/DL configuration received by the UE in a PDCCH or anePDCCH message in a first subframe or higher-layer configured subframesof one radio frame.

Example 5 may include the UE of example 4, wherein the first UL/DLconfiguration is the UL/DL configuration received by the UE in the SIB1message, and wherein the DL subframes and subframes that include a DwPTSin the radio frame are DL subframes or subframes that include a DwPTS ina plurality of possible UL/DL configurations indicated in the SIB1message.

Example 6 may include the UE of example 4, wherein the first UL/DLconfiguration is the UL/DL configuration indicated in the SIB1 message.

Example 7 may include the UE of example 4, wherein the first UL/DLconfiguration is the second UL/DL configuration that is configured byRRC signaling.

Example 8 may include the UE of example 4, wherein the first UL/DLconfiguration is the UL/DL configuration that is received by the UE inthe PDCCH or the ePDCCH message in a first subframe or higher-layerconfigured subframes of one radio frame.

Example 9 may include the UE of any of examples 1-8, further comprisingdisplay circuitry coupled with the processor.

Example 10 may include one or more non-transitory computer-readablemedia comprising instructions configured to, upon execution of theinstructions by one or more processors of a user equipment (UE), causethe UE to: identify a plurality of uplink/downlink (UL/DL)configurations applicable to subframes in a plurality of radio frames;identify an indicated UL/DL configuration received in a PhysicalDownlink Control Channel (PDCCH) or an enhanced PDCCH (ePDCCH) messagein a first subframe or higher-layer configured subframes of a radioframe in the plurality of radio frames, the indicated UL/DLconfiguration applicable to a plurality of subframes in the radio frame;identify DL subframes and subframes that include a downlink pilot timeslot (DwPTS) in the radio frame based only on a first one of the UL/DLconfigurations in the plurality of UL/DL configurations and theindicated UL/DL configuration, wherein at least one of the DL subframesor subframes that include a DwPTS are a UL subframe in a second one ofthe UL/DL configurations and the indicated UL/DL configuration;increment a running discontinuous reception (DRX) timer based only onthe identified DL subframes and subframes that include a DwPTS; andmonitor the identified DL subframes and subframes that include a DwPTSfor a PDCCH message while the DRX timer is running.

Example 11 may include the one or more non-transitory computer-readablemedia of example 10, wherein a UL/DL configuration in the plurality ofUL/DL configurations is received in a system information block type 1(SIB1) message from an eNodeB (eNB).

Example 12 may include the one or more non-transitory computer-readablemedia of example 11, wherein the instructions are further to identifythe DL subframes and subframes that include a DwPTS that are DLsubframes or subframes that include a DwPTS in a plurality of possibleUL/DL configurations indicated in the SIB1 message.

Example 13 may include the one or more non-transitory computer-readablemedia of example 11, wherein the first one of the UL/DL configurationsis the UL/DL configuration received in the SIB1 message.

Example 14 may include the one or more non-transitory computer-readablemedia of example 11, wherein the first one of the UL/DL configurationsis a UL/DL configuration indicated by radio resource control (RRC)signaling.

Example 15 may include the one or more non-transitory computer-readablemedia of example 11, wherein the first one of the UL/DL configurationsis the UL/DL configuration indicated in the PDCCH or the EPDCCH messagein the first subframe or higher-layer configured subframes of the radioframe in the plurality of radio frames.

Example 16 may include the one or more non-transitory computer-readablemedia of any of examples 10-15, wherein the DRX timer is a DRX durationtimer, a DRX inactivity timer, or a DRX retransmission timer.

Example 17 may include the one or more non-transitory computer-readablemedia of any of examples 10-15, wherein the UE is an enhancedinterference mitigation and traffic adaptation (eIMTA)-enabled UE.

Example 18 may include a method comprising: receiving, at a UE,respective indications of a plurality of uplink/downlink (UL/DL)configurations applicable to subframes of a radio frame; identifying, bythe UE based only on a first UL/DL configuration in the plurality ofUL/DL configurations, DL subframes and subframes that include a downlinkpilot time slot (DwPTS) in the subframes of the radio frame, wherein theidentified DL subframes and subframes that include a DwPTS are ULsubframes in a second UL/DL configuration in the plurality of UL/DLconfigurations; starting, by the UE, a timer related to a discontinuousreception (DRX) operation of the UE; monitoring, by the UE while thetimer related to the DRX operation of the UE is running, a PhysicalDownlink Control Channel (PDCCH) or an enhanced PDCCH (ePDCCH) for amessage only during the identified DL subframes and subframes thatinclude a DwPTS; and incrementing, by the UE, the DRX timers based onlyon the identified DL subframes and subframes that include a DwPTS in theradio frame.

Example 19 may include the method of example 18, wherein an indicationin the respective indications is received by the UE in a systeminformation block type 1 (SIB1) message from an eNodeB (eNB).

Example 20 may include the method of example 19, further comprisingidentifying, by the UE, the first UL/DL configuration based only on theindication received in the SIB1 message.

Example 21 may include the method of example 19, wherein the indicationis a first indication, and wherein: a second indication of therespective indications is received by the UE via radio resource control(RRC) signaling; and a third indication of the respective indications isreceived by the UE in a PDCCH or an ePDCCH message in a first subframeor higher-layer configured subframes of the radio frame.

Example 22 may include the method of example 21, further comprisingidentifying, by the UE, the DL subframes and subframes that include aDwPTS in the subframes of the radio frame based only on one of thesecond indication or the third indication.

Example 23 may include the method of any of examples 18-22, wherein thetimer is a DRX duration timer, a DRX inactivity timer, or a DRXretransmission timer.

Example 24 may include the method of any of examples 18-22, wherein theUE is an enhanced interference mitigation and traffic adaptation(eIMTA)-enabled UE.

Example 25 may include an apparatus comprising means to perform themethod of any of examples 18-24.

Although certain embodiments have been illustrated and described hereinfor purposes of description, this application is intended to cover anyadaptations or variations of the embodiments discussed herein.Therefore, it is manifestly intended that embodiments described hereinbe limited only by the claims.

Where the disclosure recites “a” or “a first” element or the equivalentthereof, such disclosure includes one or more such elements, neitherrequiring nor excluding two or more such elements. Further, ordinalindicators (e.g., first, second or third) for identified elements areused to distinguish between the elements, and do not indicate or imply arequired or limited number of such elements, nor do they indicate aparticular position or order of such elements unless otherwisespecifically stated.

What is claimed is:
 1. A user equipment (UE) comprising: a transceiverto: identify, in a physical downlink control channel (PDCCH) or enhancedPDCCH (ePDCCH) message received from a base station by one or moreantennas of the UE, an indication of a first time division duplexed(TDD) uplink/downlink (UL/DL) configuration of a plurality of TDD UL/DLconfigurations; and identify, in a system information block type 1(SIB1) message, an indication of a second TDD UL/DL configuration; aprocessor coupled with the transceiver, the processor to: identify asubframe that is a DL subframe based on the first TDD UL/DLconfiguration indicated by the PDCCH or ePDCCH message, wherein thesubframe is indicated as a UL subframe in the second TDD UL/DLconfiguration indicated by the SIB1 message; and monitor, in adiscontinuous reception (DRX) operation of the UE, the subframe for aPDCCH transmission transmitted by the base station.
 2. The UE of claim1, wherein the PDCCH transmission is an enhanced PDCCH (ePDCCH)transmission.
 3. The UE of claim 1, wherein the first and second TDDUL/DL configurations are related to enhanced interference mitigation andtraffic adaptation (eIMTA) operation.
 4. The UE of claim 1, wherein thesubframe is a flexible subframe of the plurality of TDD UL/DLconfigurations.
 5. The UE of claim 1, wherein the processor is furtherto base a DRX timer on the subframe.
 6. One or more non-transitorycomputer-readable media comprising instructions that, upon execution ofthe instructions by one or more processors of a user equipment (UE), areto cause the UE to: identify, in a physical downlink control channel(PDCCH) or enhanced PDCCH (ePDCCH) received from a base station, anindication of a first time division duplexed (TDD) uplink/downlink(UL/DL) configuration of a plurality of TDD UL/DL configurations;identify, in a system information block type 1 (SIB1) message, anindication of a second TDD UL/DL configuration that indicates downlinksubframes and uplink subframes; identify a subframe that is a DLsubframe based on the first TDD UL/DL configuration, wherein thesubframe is indicated as a UL subframe in the second TDD UL/DLconfiguration indicated by the SIB1 message; and monitor, in adiscontinuous reception (DRX) operation of the UE, the subframe for aPDCCH transmission transmitted by the base station.
 7. The one or morenon-transitory computer-readable media of claim 6, wherein the PDCCHtransmission is an enhanced PDCCH (ePDCCH) transmission.
 8. The one ormore non-transitory computer-readable media of claim 6, wherein thefirst and second TDD UL/DL configurations are related to enhancedinterference mitigation and traffic adaptation (eIMTA) operation.
 9. Theone or more non-transitory computer-readable media of claim 6, whereinthe instructions are further to cause the UE to base a DRX timer on theindicated downlink subframes based on the second TDD UL/DL configurationin the SIB1 message.
 10. The one or more non-transitorycomputer-readable media of claim 6, wherein the subframe is a flexiblesubframe of the plurality of TDD UL/DL configurations.
 11. A methodcomprising: identifying, by a user equipment (UE) in a physical downlinkcontrol channel (PDCCH) or enhanced PDCCH (ePDCCH) received from a basestation, an indication of a first time division duplexed (TDD)uplink/downlink (UL/DL) configuration of a plurality of TDD UL/DLconfigurations; identifying, by the UE, a subframe that is a DL subframebased on the first TDD UL/DL configuration, wherein the subframe isindicated as a UL subframe in a second TDD UL/DL configuration indicatedby a system information block type 1 (SIB1) message; and monitoring, bythe UE, the subframe for a PDCCH transmission transmitted by the basestation.
 12. The method of claim 11, wherein the PDCCH transmission isan enhanced PDCCH (ePDCCH) transmission.
 13. The method of claim 11,wherein the first and second TDD UL/DL configurations are related toenhanced interference mitigation and traffic adaptation (eIMTA)operation.
 14. The method of claim 11, further comprising basing a DRXtimer on the subframe.
 15. The method of claim 11, wherein the subframeis a flexible subframe of the plurality of TDD UL/DL configurations. 16.An apparatus comprising: means to identify, based on a physical downlinkcontrol channel (PDCCH) or enhanced PDCCH (ePDCCH) message, a first timedivision duplexed (TDD) uplink/downlink (UL/DL) configuration thatindicates downlink subframes in a radio frame; means to identify, basedon a system information block type 1 (SIB1) message, a second TDD UL/DLconfiguration that indicates downlink subframes in the radio frame;means to identify at least one subframe of the indicated downlinksubframes in the radio frame by the first TDD UL/DL configuration,wherein the at least one subframe is indicated as an uplink subframe bythe second TDD UL/DL configuration; means to monitor the at least onesubframe of the indicated downlink subframes for a PDCCH transmissionbased on the first TDD UL/DL configuration in the PDCCH message; andmeans to base a discontinuous reception (DRX) timer on the indicateddownlink subframes based on the second TDD UL/DL configuration in theSIB1 message.
 17. The apparatus of claim 16, wherein the first andsecond TDD UL/DL configurations are related to enhanced interferencemitigation and traffic adaptation (eIMTA) operation.
 18. The apparatusof claim 16, wherein the PDCCH transmission is an enhanced PDCCH(ePDCCH) transmission.
 19. The apparatus of claim 16, wherein the atleast one subframe is a flexible subframe.